Diabetes patients need to measure the blood sugar level regularly and administer insulin based on the blood sugar level to maintain a normal blood sugar level. To maintain this normal blood sugar level, diabetes patients need to measure the blood sugar level regularly, sample a small amount of blood from fingertips using a blood test apparatus, and measure the blood sugar level from this sampled blood.
The conventional blood test apparatus generally uses a needle as a means for puncturing skin (see Patent Document 1, for example). As shown in FIG. 1, conventional blood test apparatus 1 which uses a needle as a puncturing means, includes: housing 2 that forms a chassis; cylindrical body 3 having opening at one side included in housing 2; plunger 4 that moves back and forth inside cylindrical body 3; handle 5, one end of which is connected to plunger 4; latch part 6 that latches handle 5 at housing 2; spring 7 that urges handle 5 toward opening part 3a of cylindrical body 3; lancet 9 which has one end held by plunger 4 and the other end attached with blood collection needle (hereinafter “needle”) 8; holding part 11 that holds blood sensor 10 on the side of opening part 3a; and electrical circuit section 12 to which the output of sensor 10 is connected.
In order to examine blood using conventional blood test apparatus 1, the following preparation works are necessary. Blood sensor 10 and needle 8 are replaced to eliminate the influence of blood which has already been examined. In order to remove blood sensor 10 after use and attach new blood sensor 10, holding part 11 is removed and then sensor 10 after use is removed. Next, new blood sensor 10 is attached to holding part 11. Then, holding part 11 is attached to opening part 3a again. If the neighborhood of holding part 11 is stained with, for example, blood, it is cleaned.
These preparation works are troublesome for diabetes patients with poor eyesight. In addition, these works must be performed several times a day and are burdensome.
After these preparation works are done, blood test apparatus 1 is abutted on the skin of the patient, and the latching of latch part 6 is released. Then, handle 5, urged by spring 7, is propelled in the direction of arrow 14. By this release of latching of handle 5, needle 8, connected to this handle 5 via plunger 4 and lancet 9, is propelled at the same time. Needle 8 breaks through sensor 10 and punctures skin 13.
A small amount of blood flows out from punctured skin 13. The outflowing blood is guided into inside blood sensor 10. The blood guided into blood sensor 10 causes chemical change in sensor 10 according to the blood sugar level of the patient. The current produced by the chemical change is led to electrical circuit section 12, and the blood sugar level is measured. The calculated blood sugar level is displayed on display section 15. Based on the calculated blood sugar level, for example, basic data showing the amount of insulin to administer to the patient is provided.
On the other hand, an apparatus for sampling blood using laser light for the puncturing means, is also proposed (see Patent Documents 2 and 3). Use of laser light provides an advantage of making unnecessary replacement of needle and possibly alleviating the pain of the patient upon puncturing.    Patent Document 1: Japanese Patent Application Publication No. 2003-524496    Patent Document 2: Japanese Patent Application Publication No. 2004-533866    Patent Document 3: Japanese Patent Application Laid-Open No. 2004-195245